Israel has vowed to exact revenge on Palestinian militants after they launched a surprise attack on the country on Saturday, warning Hamas that they had made a 'grave mistake'. Residents living close to Israel's border with Gaza have been ordered to stay inside and others have been evacuated after Hamas militants infiltrated the country by land, sea and air and launched a fusillade of missile strikes. The Israeli prime minister Benjamin Netanyahu has vowed that the militants will pay an 'unprecedented price' after their attacks killed at least 22 Israelis, with unconfirmed further casualties reported on both sides. Speaking in...